5.2 System Representation with signal flow-graph x(n) y(n) 2 口 Source node 口 Input branch a Output node 2 口 Output branch 图522信号流图
图5.2.2 信号流图 5.2 System Representation with signal flow-graph Input branch Output branch Source node Output node
5.2 System Representation with signal flow-graph In fig. 5.2.2 we can obtained O1(1)三02(n O2(n)=O2(n Q2(m)=x(m)-a12(n)-a20D1n y(n)=b,O, (n)+6,o,(n)+bo2(n)
5.2 System Representation with signal flow-graph 1 2 2 2 2 1 2 2 1 2 1 1 2 0 2 ( ) ( 1) ( ) ( 1) ( ) ( ) ( ) ( ) ( ) ( ) ( ) n n n n n x n a n a n y n b n b n b n = − = − = − − = + + In fig. 5.2.2, we can obtained
5.2 System Representation with signal flow-graph o Digital filter structures represented in block diagram form can often be analyzed by writing down the expressions for the output signals ofeach adder as a sum of its input signals, thereby developing a set of equations relating the filter input and output signals in terms of all internal signals o Eliminating the unwanted internal variables then results in the expression for the output signal as a function of the input signal and the filter parameters that are the multiplier coefficients
5.2 System Representation with signal flow-graph Digital filter structures represented in block diagram form can often be analyzed by writing down the expressions for the output signals of each adder as a sum of its input signals, thereby developing a set of equations relating the filter input and output signals in terms of all internal signals. Eliminating the unwanted internal variables then results in the expression for the output signal as a function of the input signal and the filter parameters that are the multiplier coefficients
5.2 System Representation with signal flow-graph o Advantages of block diagram/signal flow chart representation (1) Easy to write down the computational algorithm by inspection (2)Easy to analyze the block diagram to determine the explicit relation between the output and input
5.2 System Representation with signal flow-graph Advantages of block diagram/signal flow chart representation (1) Easy to write down the computational algorithm by inspection. (2) Easy to analyze the block diagram to determine the explicit relation between the output and input
5.2 System Representation with signal flow-graph (3 Easy to manipulate a block diagram to derive other equivalent block diagrams yielding different computational algorithms (4) Easy to determine the hardware requirements (5) Easier to develop block diagram representations from the transter function directly
5.2 System Representation with signal flow-graph (3) Easy to manipulate a block diagram to derive other “equivalent” block diagrams yielding different computational algorithms. (4) Easy to determine the hardware requirements. (5) Easier to develop block diagram representations from the transfer function directly